Mounting base

ABSTRACT

The disclosure relates to a mounting base for an electric component, including, for example, first surface for receiving the electric component, and for receiving a heat load generated by the electric component, and a second surface for dissipating heat from the mounting base. The mounting base can include evaporator channels arranged in the vicinity of the first surface, condenser channels in the vicinity of the second surface and a first and second connecting part for passing fluid between the condenser channels and evaporator channels.

RELATED APPLICATION

This application claims priority under 35 U.S.C. §119 to European PatentApplication No. 10161436.0 filed in Europe on Apr. 29, 2010, the entirecontent of which is hereby incorporated by reference in its entirety.

FIELD

This disclosure relates to a mounting base for an electric component,for example, a mounting base which can conduct heat away from anelectric component.

BACKGROUND INFORMATION

In known devices an electric component is attached to a first surface ofa mounting base. In order to avoid heat generated by the electriccomponent during use from raising the temperature excessively, a secondsurface of the mounting base is cooled. In this way heat generated bythe electric component can be dissipated via the mounting base.

However, the heat load may not be evenly distributed over the mountingbase. Therefore different parts of the base can have differenttemperatures.

In case the heat load is localized on the first surface of the base, forexample, restricted to only a part of the surface area, the entiredissipation capacity of the second surface may not be efficientlyutilized because of an uneven heat distribution.

U.S. Patent Application Publication No. 2003/0155102 A1 discloses amounting base with a thermosyphon or a planar heat pipe which is usedfor distributing heat in various directions. A chamber is provided wherea fluid can boil and condense. The pressure inside the chamber canincrease to an extent than the mounting base bulges. In that case anelectric component attached to the mounting base may be bent to anextent where damage occurs to the component.

SUMMARY

A mounting base for an electric component is disclosed including a firstsurface for receiving the electric component and for receiving a heatload generated by the electric component, a second surface fordissipating heat from the mounting base and evaporator channels arrangedin the vicinity of the first surface for transferring the received heatload to a fluid in the evaporator channels, condenser channels in thevicinity of the second surface for transferring heat from the fluid inthe condenser channels to the second surface, a first connecting partfor passing the fluid from the condenser channels to the evaporatorchannels and a second connecting part for passing the fluid from theevaporator channels to the condenser channels.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments will be described in closer detail by way ofexample and with reference to the attached drawings, in which

FIGS. 1 to 3 illustrate a first exemplary embodiment of a mounting base;

FIG. 4 illustrates a second exemplary embodiment of a mounting base; and

FIG. 5 illustrates an exemplary fluid distribution in a mounting base.

DETAILED DESCRIPTION

In an exemplary embodiment of the disclosure, evaporator channels andcondenser channels can be arranged in the mounting base to make itpossible to utilize a fluid in the mounting base for receiving andpassing on a heat load generated by an electric component. In this wayheat can be efficiently distributed due to the fluid. Therefore, thedissipation capacity of the second surface of the mounting base can beutilized efficiently.

FIGS. 1 to 3 illustrate a first exemplary embodiment of a mounting base1. FIG. 1 is a side view of the mounting base 1, and FIGS. 2 and 3 arepartial cross sections of the mounting base. The illustrated mountingbase can be utilized with significant fluid pressures without anybulging that can damage components attached to the mounting base.

The mounting base 1 includes a first surface 2 for receiving one or moreelectric components 3 that generate a heat load during use. The mountingbase 1 can be utilized for efficiently cooling a plurality of electriccomponents that can be freely distributed over the first surface 2. Whenimplemented in a drive for an electric motor, such as in a frequencyconverter, for example, the electric component (or electric components)may be a power semiconductor. The generated heat load can be received bythe mounting base 1 via the first surface 2.

The heat load received by the mounting base 1 can be dissipated from themounting base via a second surface 4 of the mounting base 1. Dependingon the implementation, in various exemplary embodiments this secondsurface 4 can be provided by an apparatus or shaped in a way whichenhances the dissipation. In FIGS. 1 to 3, for example, the secondsurface includes a heat sink 5 for dissipating heat into the ambientsurroundings. Instead of a heat sink, a fin structure capable ofdissipating heat into the ambient surroundings, may be utilized. Theheat sink 5 can additionally include a plurality of fins which pass onheat into the surrounding air. If desired, in order to increase thecooling capacity, a fan may be utilized in order to generate an airflow6 between the fins, as illustrated by way of example. The direction ofthe airflow can be as illustrated, or in any suitable direction.

In order for the heat load from the electric component 3 to be evenlydistributed over the surface of the mounting base 1, the mounting basecan, for example, include evaporator channels 7, condenser channels 8, afirst connecting part 9 and a second connecting part 10 in order tocirculate fluid in the mounting base 1.

The evaporator channels 7 can be arranged in the vicinity of the firstsurface 2 to receive the heat load from the electric component 3 via thefirst surface 2, and to pass the heat load into the fluid in theevaporator channels 7. The second connecting part 10, shown in the upperend of the mounting base 1 in the example of FIGS. 1 and 2, can receivethe fluid from the evaporator channels 7 and pass the fluid on into thecondenser channels 8.

The condenser channels 8 can be arranged in the vicinity of the secondsurface 4 in order to transfer heat from the fluid in the condenserchannels to the second surface 4. The first connecting part 9, shown inthe lower end of the mounting base 1 in the example of FIGS. 1 and 2,can receive the fluid from the condenser channels 8 and pass the fluidon into the evaporator channels 9.

In FIGS. 1 and 2, the mounting base is utilized in a position where thesecond connecting part 10 is located higher than the first connectingpart 9, and the circulation of the fluid will take place due to gravityand condensation/evaporation of the fluid. See EP 2 031 332 A1 and EP 2119 993 A1, for example. No pump is therefore needed in order tocirculate the fluid. The evaporation in the evaporator channels 7 cancause an upward movement of the fluid in the evaporator channels 7, andgravity can cause a downward movement of the fluid in the condenserchannels 8. Such a circulation can be achieved at least as long as thefirst connecting part 9 is not located above the level of the secondconnecting part 10. In that case, the first and second connecting parts9 and 10 can be designed to pass on fluid from any evaporator channel toany condenser channel and vice versa. Fluid from different evaporatorchannels and different condenser channels may also be permitted to bemixed up with each other in the first and the second connecting partsbefore they are passed on.

From FIG. 3 it can be seen that the evaporator channels 7 and thecondenser channels 8 can be grouped together into at least a first group11 and a second group 12, though the number of groups is sixteen in theillustrated example. Each group can include at least one evaporatorchannel and at least one condenser channel. Such a structure can beaccomplished by extruding the mounting base 4 of an aluminum alloy, forexample, in which case the mounting base can include a single blockhaving the evaporator channels and the condenser channels formed in italready after the extrusion phase. However, in FIG. 3 it is by way ofexample assumed that the mounting base 1 includes two plates 13 and 14.The first plate can be manufactured with grooves, into which pipes canbe fitted. The pipes can include longitudinal internal walls thatseparate the evaporator channels and the condenser channels from eachother. The second plate 14 can be attached to the first plate 13 to formthe mounting base 1. The first and second plate 13 and 14, the fins ofthe heat sink 5 and the pipes may be attached to each other by providingfor example, a solder on the surfaces of these parts that come intocontact with each other. In this way, after the parts have been arrangedto contact each other in the illustrated positions, the solder can bemelted in an oven, in which case the solder melts and subsequently, whencooled, attaches the parts to each other.

In order to facilitate attachment of the electric component to themounting base by screws, for example, some of the evaporator channels ofFIG. 3 can be omitted. In that case the material thickness of themounting base is bigger at these locations, which makes it possible touse these locations for attaching said screws, for example. The solidbase material at these attachment locations can conduct heat for shortdistances, and therefore such attachment locations can be arranged indifferent parts of the mounting base in advance (before knowing exactlythe components and the sizes of the components that will be attached tothis particularly mounting base), while only those attachment locationsthat are actually needed are subsequently used by providing attachmentholes into them, for example. Consequently the attachment of componentsto the mounting base can be very simple and flexible.

FIG. 4 illustrates a second exemplary embodiment of a mounting base 1′.The embodiment of FIG. 4 is similar to the one explained in connectionwith FIGS. 1 to 3. Therefore, the embodiment of FIG. 4 will be explainedalso by pointing out the differences between these embodiments.

In FIG. 4, several subsequent pipe structures 15′ can be utilized. Thefirst and second connecting parts 9′ and 10′ can be designed to pass onfluid between these different pipe structures. Similarly to the previousembodiment, a heat sink can be provided on the second surface 4′ of themounting base 1′ for dissipating heat.

FIG. 5 illustrates fluid distribution in a mounting base, such as theone illustrated in FIGS. 1 to 3. In this figure only the electriccomponent 3, the first connecting part 9 and the second connecting part10 are shown. The evaporator channels and the condenser channels arelocated on top of each other.

FIG. 5 illustrates a situation where the first and second connectingparts 9 and 10 have a structure that allows fluid from differentevaporator channels, and correspondingly, different condenser channels,to mix up with each other and to be passed on via any one of thecondenser channels, and correspondingly, evaporator channels. It can beseen that as the fluid also circulates sideways, the cooling capacity ofthe entire second surface can be utilized efficiently. In this way thedimensions of the mounting base can be increased both longitudinally andtransversally. The spaces between the channels may be dimensioned insuch a way that electric or other components can be attached by screws,for instance, in the spaces between the channels.

In the previous explanation the term ‘fluid’ has been used generally toindicate any medium suitable for use in the described mounting base. Thefluid may be a liquid or a gas, and in many implementations, the fluidcan be in liquid state in certain parts of the mounting base while itcan be in a gas state in other parts of the mounting base.

Thus, it will be appreciated by those having ordinary skill in the artthat the present disclosure can be embodied in other specific formswithout departing from the spirit or essential characteristics thereof.The presently disclosed embodiments are therefore considered in allrespects to be illustrative and not restricted. The scope of thedisclosure is indicated by the appended claims rather than the foregoingdescription and all changes that come within the meaning and range andequivalence thereof are intended to be embraced therein.

1. A mounting base for an electric component, comprising: a firstsurface for receiving the electric component and for receiving a heatload generated by the electric component; a second surface fordissipating heat from the mounting base; evaporator channels arranged ina vicinity of the first surface for transferring received heat load to afluid in the evaporator channels; condenser channels in a vicinity ofthe second surface for transferring heat from fluid in the condenserchannels to the second surface; a first connecting part for passingfluid from the condenser channels to the evaporator channels; and asecond connecting part for passing fluid from the evaporator channels tothe condenser channels.
 2. A mounting base according to claim 1, whereinthe second surface comprises: at least one of a heat sink and a finstructure for dissipating heat into air.
 3. A mounting base according toclaim 1, wherein the evaporator channels and the condenser channels aregrouped together into at least a first group and a second group, eachgroup including at least one evaporator channel and at least onecondenser channel.
 4. A mounting base according to claim 3, wherein thefirst connecting part is arranged for conducting fluid from one or morecondenser channels of the first group into one or more evaporatorchannels of the at least first and second groups; and the secondconnecting part is arranged for conducting fluid from one or moreevaporator channels of the first group into one or more condenserchannels of the at least first and second groups.
 5. A mounting baseaccording to claim 1, wherein the mounting base formed with an aluminumalloy or a copper alloy.